There are 150 people in a school canteen.
Two fifths of the people in the canteen are year 11 students.
The number of year 11 students in the canteen is four times the number of year 10 students.
The rest of the people in the canteen are year 9 students.
the number of year 9 students : the number of year 10 students = n:1 n : 1\,n:1
Work out the value of nnn.
You must show how you get your answer.
249 exam-style questions on OCR GCSE Maths Writing and Simplifying Ratio. Each one has a worked solution and a mark scheme showing where the marks go.